1. Field of the Invention
This invention relates to an apparatus and method for recording and reproducing digital video and audio data, and particularly to a video and audio data recording apparatus, a video and audio data recording method, a video and audio data reproducing apparatus, and a video and audio data reproducing method that enable supporting multi-format without limiting a video data format, an audio data format and a format for multiplexing these formats.
2. Description of the Related Art
As more and more video and audio contents are transmitted in a digital format or distributed as packages, AV equipments for recording and reproducing these digital video and audio contents are being popularized. Recording media for such contents include magnetic disks, optical discs or magnetic tapes. Particularly a system with a randomly accessible recording medium not only records and reproduces video and audio contents but also often performs special reproduction utilizing its random accessibility. DVD players, DVD recorders and hard disk recorders are typical examples of such a system.
In order to realize special reproduction utilizing the random accessibility, it is necessary to not only record video and audio contents like a file handled on a personal computer but also provide a certain measure to analyze the digital video and audio data and manage the digital audio and video data using a necessary unit for realizing special reproduction. Practically, the above-described system has such a measure.
However, the format of and compression method for video and audio contents to be recorded are usually limited and a necessary measure to realize the above-described special reproduction or the like is constructed within the limited framework. As a result, limitation of video and audio contents, limitation of recording/reproduction processing methods for video and audio contents, and limitation of recording media are necessary and a single system matching these limitations must be constructed.
Although some of such systems accept input of plural video formats and plural audio formats, video and audio data are re-encoded to a dedicated format to which the systems are conformable. Even if the systems are conformable to plural formats, they are only conformable to specified plural formats. The re-encoding causes deterioration in image and sound quality, and the quality of inputted video and audio contents cannot be maintained when these contents are recorded.
In this manner, the conventional systems are only conformable to a specified video format, a specified audio format and a specified video and audio multiplexing format. To flexibly support other formats, separate AV equipments conformable to these formats must be prepared. This causes much inconvenience.
Even when plural formats are supported, if a re-encoding system is used, the problem of deterioration in original image quality arises.